Knesset Research and Information Center: The survey does not properly represent the share of young people, Arabs and residents of the north in the entire Israeli population

• Serological tests in a laboratory in Israel

  Photo: 

  Yossi Zeliger

It is feared that the antibody survey (the serological survey) conducted by the Ministry of Health in collaboration with the HMOs, does not represent the entire population and has under-representation for the young population, the Northern District and the Arabs. 

This became clear from a report by the Knesset Research and Information Center. The center examined the work process on the survey, which covers 75,000 people (0.8% of the population). 

The survey is designed to estimate at the national level the extent of people who have been exposed to the corona virus and have developed antibodies to it, as well as to establish differences between different populations. In doing so it is supposed to help the intelligent management of dealing with the plague.

Archive photo: Knesset Channel

The survey includes 191 localities, 13 of which were the focus of an outbreak of corona and the rest nationwide. It was scheduled to launch in early June but actually began on the 29th of the month. 

By August 9, 48,644 people participated in the survey, which is about two-thirds of the numerical target of all respondents. The survey report indicates that he may not have represented the population accurately. 

Investigators from the Knesset's Research and Information Center were unable to obtain answers as to whether or not the Ministry of Health acted to correct the under-representation, and whether it succeeded. 

The survey, which includes taking a blood test from people who are already cashed in HMO clinics for blood tests, has 59% women, while it was planned that there would be an equal distribution between the sexes.

Moreover, the survey also has an under-representation of young people, while the elderly population is over-represented. The rate of those surveyed from Jewish localities exceeds their rate in the population, while the rate of those sampled from non-Jewish localities is lower than their share in the population. The Haifa district is under-represented and it is not clear whether the socio-economic background of those surveyed has been examined.

"Reliability cannot be conveniently replaced"

Prof. Danny Pepperman, National Statistician and Director of the CBS: "The survey proposed by the Ministry of Health is called a 'convenience sample', and there is no doubt that it is very convenient to sample in this way since the samples come for blood samples anyway. But with all due respect, reliability can not be replaced comfortably. " 

MK Dr. Yifat Shasha-Biton, chairman of the Corona committee in the Knesset that commissioned the report, responded as expected to the survey despite the shortcomings: . 

"The survey gives an indication of the proportion of people who were probably exposed to the virus, at the same time it was performed - but in order to get an in-depth picture and identify trends over time, it should be performed for any period of time, similar to other countries."